Lake Success is a village in the Town of North Hempstead in Nassau County, on the North Shore of Long Island, in New York, United States. The population was 2,828 at the time of the 2020 census. The Incorporated Village of Lake Success was the temporary home of the United Nations from 1946 to 1951, occupying the headquarters of th…Lake Success is a village in the Town of North Hempstead in Nassau County, on the North Shore of Long Island, in New York, United States. The population was 2,828 at the time of the 2020 census. The Incorporated Village of Lake Success was the temporary home of the United Nations from 1946 to 1951, occupying the headquarters of the Sperry Gyroscope Company on Marcus Avenue.